1. Field of the Invention
The present invention relates to axial flow turbomachines, such as the turbojet engines used to power civil or military aircraft, and more particularly relates to the fixing of rotor blades axially in position on the disk of a turbomachine rotor.
The application of the invention to turbojet engines is only one example of its use, and in no way limits the range of possible uses of the fixing arrangement in accordance of the invention.
2. Summary of the Prior Art
In the construction of gas turbine engines, such as turbojet engines, the fixing of rotor blades is often effected by insertion of the root of the blade into a socket in the periphery of the rotor disk, and the axial positioning of the blades is achieved by means of a 360.degree. spring washer which is located in the grooves formed by undercut projections machined in the upstream face of the disk and on an upstream face of the roots of the blades.
However, during operation of the turbomachine, the blades exert a substantial force in a downstream direction and, as a result, clamp the spring washer against the upstream face of the disk. At the same time, the washer expands in thickness and diameter as a result of the changes in temperature and centrifugal force. This phenomenon is accentuated when the blades are mounted in sockets which are inclined relative to the engine axis. The combined action of these various phenomena produces unacceptable stresses on the periphery of the disk and on the spring washer, and shortens the life of these elements.
It is an object of the invention, therefore, to avoid these drawbacks by proposing an alternative solution for the axial fixing of the blades.